Self authentication of color images through discrete cosine transformation (SADCT)

In this paper a DCT based steganographic technique in frequency domain, termed as SADCT has been proposed for authentication of color images. The cover image transformed into the time domain using 8×8 mask in row major order using DCT resulting its corresponding frequency components. Highest frequency values are fetched from red and green components of transformed RGB matrix as watermark. Using a secret key and a hash function watermarks are embedded into blue components of the cover image in spatial domain. Experimental results are computed and compared with the existing steganographic techniques like IAFDDFTT[1] and SAWT [9] in terms of Mean Square Error (MSE), Peak Signal to Noise Ratio (PSNR), Standard Deviation (SD) and Image Fidelity (IF) which show better performances in SADCT.